Patterned stimulation intensity for neural stimulation

ABSTRACT

One aspect of the present disclosure relates to a system that can modulate the intensity of a neural stimulation signal over time. A pulse generator can be configured to generate a stimulation signal for application to neural tissue of an individual and modulate a parameter related to intensity of a pattern of pulses of the stimulation signal over time. An electrode can be coupled to the pulse generator and configured to apply the stimulation signal to the neural tissue. A population of axons in the neural tissue can be recruited with each pulse of the stimulation signal.

This application is a Continuation of U.S. patent application Ser. No.16/918,134, filed on Jul. 1, 2020, which is a Continuation of U.S.patent application Ser. No. 16/175,967, filed Oct. 31, 2018, which is aContinuation of U.S. patent application Ser. No. 15/104,589, filed Jun.15, 2016, which is a U.S. National Stage under 35 USC 371 patentapplication claiming priority to Serial No. PCT/US2014/070435, filed onDec. 16, 2014, which is a Continuation of Patent Application Serial No.PCT/US2013/075329, filed Dec. 16, 2013. Each of which is herebyincorporated by reference for all purposes.

TECHNICAL FIELD

The present disclosure relates generally to neural stimulation and, morespecifically, to systems and methods that can modulate the intensity ofa pattern of pulses in a neural stimulation signal.

BACKGROUND

Through neural stimulation, an electrical signal can activate orsuppress a part of an individual nervous system to replace and/oraugment a biological function of the individual (e.g., a motor function,a sensory function, an autonomic function, an organ function, and/or acognitive function). Traditionally, the electrical signal has includedtrains of identical electric pulses (e.g., constant frequency,amplitude, and interpulse interval), each providing a regular intensitystimulation. However, these trains of identical electric pulses often donot mimic normal biological functions. For example, when responding to asensory input, normal afferent neurons can generate non-constantpatterns of action potentials synchronously on a population of axons.When a regular train of identical pulses is applied to these afferentneurons, a corresponding regular train of synchronous action potentialscan be transmitted to the brain. The regular train of action potentialscan be interpreted by the brain as foreign, resulting in a tinglingsensation or other abnormal sensory perception.

SUMMARY

The present disclosure relates generally to neural stimulation and, morespecifically, to systems and methods that can modulate the intensity(e.g., strength and/or timing) of a pattern of pulses in a neuralstimulation signal. For example, the neural stimulation signal caninclude a train of pulses, and a parameter associated with the intensityof a pattern of these pulses can be modified over time. The neuralstimulation signal with such patterned stimulation intensity (or“Ψ-stim”) can mimic normal neurological functions, allowing the neuralstimulation signal to affect different biological functions, includingsensory functions (e.g., perception), autonomic functions, motorfunctions, and/or cognitive function.

In one aspect, the present disclosure can include a system that canmodulate the intensity (e.g., strength and/or timing) of a neuralstimulation signal over time. A pulse generator can be configured togenerate a stimulation signal for application to neural tissue of anindividual and modulate a parameter related to intensity of a pattern ofpulses of the stimulation signal over time. An electrode can be coupledto the pulse generator and configured to apply the stimulation signal tothe neural tissue. For example, the modulation of the intensity overtime can lead to different populations of axons in the neural tissue tobe recruited based on the modulation of the intensity.

In another aspect, the present disclosure can include a method forneural stimulation signal. A parameter related to an intensity (e.g.,strength and/or timing) of a pulse of the stimulation signal ismodulated with time. Different populations of axons in the neural tissuecan be recruited with each pulse of the stimulation signal. A desiredbodily function can be affected in the individual based on thestimulation signal. In some instances, the method can involveidentifying an individual in need of neural stimulation and applying theneural stimulation signal to the individual in need of the neuralstimulation. For example, in the instance of a diseased individual, themethod can include identifying the individual suffering from thediseased condition.

In a further aspect, the present disclosure can include a device thatcan modulate the intensity (e.g., strength and/or timing) of a neuralstimulation signal over time. A pulse generator can be configured to afeedback signal based on the neural stimulation signal. For example, thefeedback signal can be a physiological signal, a sensor signal, an inputsignal, or the like. The pulse generator can be further configured tomodulate a parameter related to intensity of a pattern of pulses of thestimulation signal based on the feedback signal.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features of the present disclosure will becomeapparent to those skilled in the art to which the present disclosurerelates upon reading the following description with reference to theaccompanying drawings, in which:

FIG. 1 is a block diagram showing a system that can modulate theintensity of a neural stimulation signal in accordance with an aspect ofthe present disclosure;

FIG. 2 is a block diagram showing a receiver that can be part of thesystem of FIG. 1 to receive a feedback signal that can be utilized inthe modulation of the intensity of the neural stimulation signal;

FIG. 3 is a graph showing examples of modulations of the intensity ofthe neural stimulation signal that can be done by the system shown inFIG. 1 ;

FIGS. 4 and 5 are example illustrations of electrodes that can be partof the system shown in FIG. 1 ;

FIG. 6 is a process flow diagram illustrating a method for neuralstimulation in accordance with another aspect of the present disclosure;

FIG. 7 is a process flow diagram illustrating a method for modulatingthe intensity of a signal used for the neural stimulation in the methodshown in FIG. 6 ; and

FIG. 8 is a process flow diagram illustrating a method for affecting adesired bodily function with the neural stimulation in the method shownin FIG. 6 .

DETAILED DESCRIPTION I. Definitions

In the context of the present disclosure, the singular forms “a,” “an”and “the” can also include the plural forms, unless the context clearlyindicates otherwise. The terms “comprises” and/or “comprising,” as usedherein, can specify the presence of stated features, steps, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, steps, operations, elements,components, and/or groups. As used herein, the term “and/or” can includeany and all combinations of one or more of the associated listed items.Additionally, although the terms “first,” “second,” etc. may be usedherein to describe various elements, these elements should not belimited by these terms. These terms are only used to distinguish oneelement from another. Thus, a “first” element discussed below could alsobe termed a “second” element without departing from the teachings of thepresent disclosure. The sequence of operations (or acts/steps) is notlimited to the order presented in the claims or figures unlessspecifically indicated otherwise.

As used herein, the term “neural stimulation” can refer to thetherapeutic activation or suppression of at least a portion of anindividual nervous system to replace, restore, and/or augment abiological function via a stimulation signal. In some instances, thestimulation signal can be applied to the individual's neural tissuethrough one or more electrodes.

As used herein, the term “stimulation signal” can refer to a signal thatcan activate or suppress a portion of an individual's nervous system toreplace, restore, and/or augment a biological function of theindividual. For example, the stimulation signal can include one or moreof an electrical signal, a magnetic signal, an optical signal, anopto-genetic signal, a chemical signal, or the like. In some instances,the stimulation signal can include a train of pulses.

As used herein, the term “pulse” can refer to a non-sinusoidal waveformof current and/or voltage. In some instances, a pulse can becharge-balanced. In other instances, a plurality of pulses can bearranged in one or more patterns of pulses. Example shapes of a pulsecan include square, rectangular, ramp, logarithmic, exponential, and thelike.

As used herein, the term “biological function” can refer to a processthat takes place within an individual's body controlled by the nervoussystem. Examples of biological functions can include motor functions,sensory functions, autonomic functions, organ functions, and cognitivefunctions. The terms “biological function” and “bodily function” can beused interchangeably herein.

As used herein, the term “electrode” can refer to one or more electricalconductors that contact(s) a portion of an individual's body to delivera stimulation signal. In some instances, each individual electricalconductor can be referred to as a “contact”. For example, an electrodecan be a multi-contact electrode and/or a plurality of single-contactelectrodes.

As used herein, the term “neural tissue” can refer to a population ofaxons that can react to stimuli and conduct impulses to various organsor tissues in the body that bring about a response to the stimuli. Theneural tissue can include, for example, populations of central nervoussystem axons (e.g., axons within the brain and/or the spinal cord) orpopulations of peripheral nervous system axons (e.g., motor axons,autonomic axons, and/or sensory axons). The terms “axon” and “neuralfiber” can be used interchangeably herein.

As used herein, the term “patterned stimulation intensity” (or “Ψ-stim”)can refer to a variation of one or more stimulation parameter related tothe intensity of a pattern of pulses in a neural stimulation signal. Inone example, “patterned intensity stimulation” can refer topopulation-based encoding of neural tissue because the variation of theone or more stimulation parameters can lead to recruitment of differentpopulations of axons within the neural tissue. The terms “patternintensity modulation” and “patterned stimulation intensity” can be usedinterchangeably herein.

As used herein, the term “intensity” of the stimulation signal can referto the strength and/or timing of the stimulation signal. In someinstances, the intensity can correspond to the number of neural fibersthat are recruited by a pulse and/or pattern of pulses of a stimulationsignal.

As used herein, the term “stimulation parameter” can refer to aparameter of a pulse and/or pattern of pulses associated with theintensity of a stimulation signal. Examples of stimulation parameterscan include amplitude, pulse width, interpulse interval, pulse shape(e.g., square, rectangular, exponential, logarithmic, ramp, etc.),parameters affecting pulse shape, recharge phase amplitude, rechargedelay, and the like. The terms “stimulation parameters,” “intensityparameters,” and “pulse parameters” can be used interchangeably herein.

As used herein, the term “individual” can refer to any warm-bloodedorganism including, but not limited to, a human being, a pig, a rat, amouse, a dog, a cat, a goat, a sheep, a horse, a monkey, an ape, arabbit, a cow, etc. The terms “individual,” “subject,” “patient,” and“user” can be used interchangeably herein unless otherwise indicated.

II. Overview

The present disclosure relates generally to neural stimulation and, morespecifically, to systems and methods that can modulate the intensity(e.g., strength and/or timing) of a pattern of pulses in a neuralstimulation signal. For example, a stimulation signal for application toneural tissue of an individual can be generated and a parameter relatedto intensity of a pattern of pulses of the stimulation signal can bemodulated over time. When the stimulation signal is applied to theneural tissue, a population of axons in the neural tissue can berecruited with each pulse of the stimulation signal.

The neural stimulation with patterned stimulation intensity (or“Ψ-stim”) in the peripheral nervous system and/or the central nervoussystem can affect different biological functions, including sensoryfunctions (e.g., perception), autonomic functions, motor functions,organ functions, and/or cognitive functions. For example, the neuralstimulation can be used to affect a biological function in a normalable-bodied individual; an amputee; a paralyzed individual; or adiseased individual, such as an individual suffering from an autonomic,motor, and/or sensory deficit. In one example, the biological functioncan include sensory restoration in amputees or paralyzed individuals.The sensory restoration can include providing a “virtual” sensation toreplace the missing biological sensation. In another example, thebiological function can include providing an artificial sensation to anable-bodied individual by stimulating the median, ulnar and/or radialnerves for touch-enabled virtual reality, user interfaces, clinicaldiagnoses, mechanical diagnoses, robotic control, and/or telepresence.

Other examples of the biological function can include modulation ofpain, such as, for example, modulating the individual's perception ofpain. In a further example, the biological function can includerestoration or augmentation of taste, smell, hearing, vision or touch.In yet another example, the biological function can include regulationof swallowing. In still another example, the biological function caninclude regulation of gastric reflux. In yet another example, thebiological function can include regulation of blood pressure, appetite,or the like. In yet another example, the biological function can includerestoration of sexual sensation or enhancement of sexual sensation. In afurther example, the biological function can include genito-urinaryregulation, such as relieving incontinence, regulating voiding, otherbladder functions, and the like. In another example, the biologicalfunction can include improving lactation for breastfeeding. In anotherexample, the biological function is restoring sensory perception ofremoved or missing tissue in an individual. In yet another example,sensory perception of removed breast tissue can be restored in anindividual who has undergone a mastectomy. In still another example, thebiological function can include regulation of a movement disorder. Forthe different biological functions, electrodes can be placed indifferent areas of the individual's body and the patterned intensitymodulation of the stimulation signal can lead to recruitment ofdifferent populations of axons within the neural tissue.

III. Systems

One aspect of the present disclosure can include a system that canmodulate the intensity of a neural stimulation signal. Although notwishing to be bound by theory, it is believed that by modulating theintensity of the neural stimulation signal, the neural stimulationsignal can mimic normal neurological functions of an individual moreclosely than traditional stimulation with a regular train of identicalpulses. When the stimulation signal is applied to the neural tissue, themodulation can allow different populations of axons in the neural tissueto be recruited with each pulse of the stimulation signal.

FIG. 1 illustrates an example of a system 10 that can modulate theintensity (e.g., strength and/or timing) of a neural stimulation signal,according to an aspect of the present disclosure. The system 10 caninclude a pulse generator 12 to generate and modulate a stimulationsignal (SS) and an electrode 14 to apply the stimulation signal (SS) toan individual's neural tissue. The stimulation signal (SS), in someexamples, can be a time-varying electrical signal. In some examples, thepulse generator 12 can employ patterned stimulation intensity (or“Ψ-stim”) to vary one or more parameters related to intensity of thestimulation signal (SS). As noted, the neural stimulation with patternedstimulation intensity can activate and/or suppress different biologicalfunctions, including sensory functions (e.g., perception), autonomicfunctions, motor functions, organ functions, and/or cognitive functions,of a normal individual, an amputee, a paralyzed individual, a diseasedindividual, or the like.

The pulse generator 12 can be a device configured to generate thestimulation signal (SS). In some instances, the pulse generator 12 alsocan be configured to modulate a parameter related to intensity of apattern of pulses of the stimulation signal. As an example, the pulsegenerator 12 can modulate the parameter related to the intensity overtime. In another example, the pulse generator 12 can generate and/ormodulate the stimulation signal (SS) based on based on a desired bodilyfunction. As another example, shown in FIG. 2 , the pulse generator 12can be configured to generate and/or modulate the stimulation signal(SS) based on an input related to the desired bodily function.

In the example shown in FIG. 2 , the pulse generator 12 can be coupledto a receiver 22. In some instances, the pulse generator 12 and thereceiver 22 can be embodied as components of a single device. In otherinstances, the pulse generator 12 and the receiver 22 can each beembodied as separate devices coupled together via a wired and/orwireless connection that facilitates communication between the pulsegenerator 12 and the receiver 22.

One or more functions of pulse generator 12 and/or the receiver 22 canbe implemented by computer program instructions. These computer programinstructions can be provided to a processor of a general purposecomputer, special purpose computer, and/or other programmable dataprocessing apparatus to produce a machine, such that the instructions,which execute via the processor of the computer and/or otherprogrammable data processing apparatus, create a mechanism forimplementing the functions of the pulse generator 12 and/or the receiver22.

These computer program instructions can also be stored in anon-transitory computer-readable memory that can direct a computer orother programmable data processing apparatus to function in a particularmanner, such that the instructions stored in the non-transitorycomputer-readable memory produce an article of manufacture includinginstructions, which implement the functions of the pulse generator 12and/or the receiver 22.

The computer program instructions can also be loaded onto a computer orother programmable data processing apparatus to cause a series ofoperational steps to be performed on the computer or other programmableapparatus to produce a computer-implemented process such that theinstructions that execute on the computer or other programmableapparatus provide steps for implementing the functions of the componentsspecified in the block diagrams and the associated description.

Accordingly, the pulse generator 12 and/or the receiver 22 can beembodied at least in part in hardware and/or in software (includingfirmware, resident software, micro-code, etc.). Furthermore, aspects ofthe system 10 can take the form of a computer program product on acomputer-usable or computer-readable storage medium havingcomputer-usable or computer-readable program code embodied in the mediumfor use by or in connection with an instruction execution system. Acomputer-usable or computer-readable medium can be any non-transitorymedium that is not a transitory signal and can contain or store theprogram for use by or in connection with the instruction or execution ofa system, apparatus, or device. The computer-usable or computer-readablemedium can be, for example but not limited to, an electronic, magnetic,optical, electromagnetic, infrared, or semiconductor system, apparatusor device. More specific examples (a non-exhaustive list) of thecomputer-readable medium can include the following: a portable computerdiskette; a random access memory; a read-only memory; an erasableprogrammable read-only memory (or Flash memory); and a portable compactdisc read-only memory.

Such functions of the receiver 22 can include receiving an input signal(FS) and transmitting data related to the input signal (PFS) to thepulse generator 12. In some instances, the receiver 22 can be configuredto perform signal processing on the input signal (FS). For example, thesignal processing employed by the receiver 22 can transform the inputsignal (FS) into data related to the input signal (PFS). The datarelated to the input signal (PFS) can be transmitted to the pulsegenerator 12.

The pulse generator 12 can be configured to generate and/or modulate thestimulation signal (SS) based on the data related to the input signal(FS). For example, the input signal (FS) can include a user input, afeedback signal input from the neural tissue or other tissue, a sensorsignal input, a time input, etc. As another example, the input signalcan include an input related to a stimulation paradigm defining amodulation pattern or envelope that can be employed by the pulsegenerator 12.

In either system 10 of FIG. 1 or system 20 of FIG. 2 , the stimulationsignal (SS) generated by the pulse generator 12 can include a pluralityof pulses. In some instances, the plurality of pulses can becharge-balanced (cathodic first and/or anodic first). In otherinstances, a pattern of the plurality of pulses can be charge-balanced,even if the individual pulses are not charge-balanced. In still otherinstances, the plurality of pulses need not be charge-balanced, but canbe employed over a time period that is sufficiently short so that anyelectrochemical reactions products generated are not generated in aquantity large enough to cause damage to surrounding tissue or theelectrode 14.

The pulse generator 12 can modulate the stimulation signal (SS) bymodulating one or more pulse parameters related to intensity of thestimulation signal (SS). The modulation of the one or more pulseparameters of the stimulation signal (SS) related to intensity canrecruit a different population of axons with each pulse. For example,the pulse generator 12 can vary the pulse parameter related to intensityfor each of the pulses. As another example, the pulse generator 12 canvary the pulse parameter related to intensity for a plurality of pulsesaccording to a stimulation paradigm that defines a modulation pattern ormodulation envelope. The modulation pattern or modulation envelope canbe any shape representing a time-varying alternation of one or morepulse parameters related to intensity of the stimulation signals (SS).Example shapes of the modulation pattern or modulation envelope caninclude a sinusoid, a triangle, a trapezoid, or the like. In someinstances, a single pulse parameter related to intensity can bemodulated by the pulse generator 12. In other instances, different pulseparameters related to intensity can be modulated by the pulse generator12 at different times. In still other instances, a plurality ofdifferent pulse parameters related to intensity can be modulated by thepulse generator 12 at the same time (or substantially the same time).

The one or more stimulation parameters can be any parameter of a pulseand/or a pattern of pulses that relates to the intensity of thestimulation signal. Examples of stimulation parameters related tointensity can include amplitude, pulse width, interpulse interval, pulseshape, parameters affecting pulse shape, recharge phase amplitude,recharge delay, and the like. Other examples of intensity parameters caninclude a parameter related to the modulation envelope (e.g., shape,frequency, amplitude, etc.).

FIG. 3 shows examples of different modulations that can be done to aseries of pulses by the pulse generator 12 as a graph of a feature ofthe pulse train (e.g., pulse intensity) over time. The graph of FIG. 3is an exemplary schematic illustrating different parameters of astimulation signal (SS) that can be modulated. In FIG. 3 , a baselinesignal is shown at 32. The amplitude of the baseline signal can bevaried at 34. The interpulse interval can be varied at 36. Theinterpulse interval and the amplitude/shape can be varied in combinationat 38. At elements 34 and 36, a single parameter is varied for the groupof pulses. At 38, a parameter (interpulse interval) is varied for thegroup of pulses and a parameter (amplitude) is varied for individualpulses. Additional parameters can be modulated that are not illustratedin FIG. 3 (e.g., any parameter of a pulse and/or a pattern of pulsesthat relates to the intensity of the stimulation signal, such as pulsewidth, parameters affecting pulse shape, recharge phase amplitude,recharge delay, a parameter related to the modulation envelope (e.g.,shape, frequency, amplitude, etc.).

Referring again to FIGS. 1 and 2 , the electrode 14 can be coupled tothe pulse generator 12 to receive the stimulation signal (SS)transmitted by the pulse generator. The electrode 14 can interface withthe neural tissue of the individual to deliver the stimulation signal(SS) to the neural tissue to affect the desired biological function. Theelectrode 14 can be placed transcutaneously, subcutaneously, or directlyon the neural tissue to be stimulated. In some instances, the neuraltissue that the electrode 14 can interface with can include a portion ofthe central nervous system (e.g., for deep brain stimulation, spinalstimulation, or the like). For example, deep brain stimulation can beused to treat movement disorders, such as essential tremor orParkinson's disease. In another example, deep brain stimulation and/orspinal cord stimulation can also be used to manage pain. In otherinstances, the neural tissue that the electrode can interface with caninclude a portion of the peripheral nervous system (e.g., a nerve (e.g.,an afferent nerve, an efferent nerve, and/or an autonomic nerve) and/organglia).

In some instances, the electrode 14 can include a set of multiplecontacts that can include N electrode contacts, where N is a positiveinteger greater than or equal to two. For example, the pulse generator12 can modulate the timing and the strength of each pulse in thestimulation signal (SS) between the multiple contacts to alter anelectric field delivered to the neural tissue by the electrode 14. Insome instances, as schematically illustrated in FIG. 4 , the electrode14 (e.g., an electrode array) can include a plurality of single-contactelectrodes 42 a-d. For example, the plurality of electrodes can bebetween or within fascicles. In another example, the electrodes can belocated within the brain and/or the spinal cord. In other instances, asschematically illustrated in FIG. 5 , the electrode 14 can include amulti-contact electrode (e.g., a nerve cuff electrode, a spiralelectrode, etc.) with a plurality of contacts 42 m-i.

As noted, the stimulation signal (SS) with patterned stimulationintensity from the pulse generator 12 can affect different biologicalfunctions, including sensory functions (e.g., perception), autonomicfunctions, motor functions, organ functions, and/or cognitive functions.In one example, the biological function can include sensory restorationin amputees or paralyzed individuals. In another example, the biologicalfunction can include modulation of pain. In a further example, thebiological function can include restoration of taste. In yet anotherexample, the biological function can include regulation of swallowing.In still another example, the biological function can include regulationof gastric reflux. In yet another example, the biological function caninclude regulation of blood pressure, appetite, or the like. In still afurther example, the biological function can include restoration ofhearing, vision, or the like. In yet another example, the biologicalfunction can include restoration of sexual sensation or enhancement ofsexual sensation. In a further example, the biological function caninclude genito-urinary regulation, such as relieving incontinence,regulating voiding, and the like. In yet another example, sensoryperception of removed breast tissue can be restored in an individual whohas undergone a mastectomy. In still another example, the biologicalfunction can include regulation of a movement disorder. For thedifferent biological functions, electrodes can be placed in differentareas of the individual's body and the patterned intensity modulation ofthe stimulation signal can lead to recruitment of different populationsof axons within the neural tissue.

IV. Methods

Another aspect of the present disclosure can include methods formodulating the intensity (e.g., strength and/or timing) of a neuralstimulation signal. An example of a method 60 for neural stimulation toaffect a desired bodily function is shown in FIG. 6 . Another example ofa method 70 for modulating the intensity of a signal used for the neuralstimulation is shown in FIG. 7 . A further example of a method 80 foraffecting a desired bodily function with the neural stimulation is shownin FIG. 8 . In some instances, the method can involve identifying anindividual in need of neural stimulation and applying the neuralstimulation signal to the individual in need of the neural stimulation.For example, in the instance of a diseased individual, the method caninclude identifying the individual suffering from the diseasedcondition.

The methods 60-80 of FIGS. 6-8 , respectively, are illustrated asprocess flow diagrams with flowchart illustrations. For purposes ofsimplicity, the methods 60-80 are shown and described as being executedserially; however, it is to be understood and appreciated that thepresent disclosure is not limited by the illustrated order as some stepscould occur in different orders and/or concurrently with other stepsshown and described herein. Moreover, not all illustrated aspects may berequired to implement the methods 60-80.

One or more blocks of the respective flowchart illustrations, andcombinations of blocks in the block flowchart illustrations, can beimplemented by computer program instructions. These computer programinstructions can be stored in memory and provided to a processor of ageneral purpose computer, special purpose computer, and/or otherprogrammable data processing apparatus to produce a machine, such thatthe instructions, which execute via the processor of the computer and/orother programmable data processing apparatus, create mechanisms forimplementing the steps/acts specified in the flowchart blocks and/or theassociated description. In other words, the steps/acts can beimplemented by a system comprising a processor that can access thecomputer-executable instructions that are stored in a non-transitorymemory.

The methods 60-80 of the present disclosure may be embodied in hardwareand/or in software (including firmware, resident software, micro-code,etc.). Furthermore, aspects of the present disclosure may take the formof a computer program product on a computer-usable or computer-readablestorage medium having computer-usable or computer-readable program codeembodied in the medium for use by or in connection with an instructionexecution system. A computer-usable or computer-readable medium may beany non-transitory medium that can contain or store the program for useby or in connection with the instruction or execution of a system,apparatus, or device.

Referring to FIG. 6 , an aspect of the present disclosure can include amethod 60 for neural stimulation to affect a bodily function. At 62, astimulation signal (e.g., SS) can be generated (e.g., by pulse generator12) for application to neural tissue of an individual. The neural tissuecan include central nervous system tissue and/or peripheral nervoussystem tissue (motor nerves, sensory nerves, and/or autonomic nerves).The stimulation signal can be configured with parameters tailored forthe desired biological function. For example, the stimulation signal caninclude a plurality of pulses that can be arranged in patterns. Asnoted, the neural stimulation can be applied to a normal individual, anamputee, a paralyzed individual, a diseased individual, or the like. Forexample, the stimulation signal can include a plurality of pulses (e.g.,arranged in a modulation pattern or envelope).

At 64, an intensity parameter of a pattern of pulses in the stimulationsignal can be modified (e.g., by pulse generator 12). The modificationcan be based on the desired bodily function. For example, one or moreparameters related to the intensity of the stimulation signal can bemodulated. The modulation of the one or more pulse parameters of thestimulation signal related to intensity can recruit a differentpopulation of axons with each pulse. For example, the parameter relatedto intensity can be varied for each of the pulses. As another example,the pulse parameter related to intensity can be varied for a pluralityof pulses according to the modulation pattern or modulation envelope(e.g., of any shape representing a time-varying alternation of one ormore pulse parameters related to intensity of the stimulation signal).In some instances, a single parameter related to intensity can bemodulated. In other instances, different parameters related to intensitycan be modulated at different times. In still other instances, aplurality of different pulse parameters related to intensity can bemodulated by the pulse generator 12 at the same time (or substantiallythe same time). The one or more stimulation parameters can be anyparameter of a pulse and/or a pattern of pulses that relates to theintensity of the stimulation signal. Examples of stimulation parametersrelated to intensity can include amplitude, pulse width, interpulseinterval, pulse shape, parameters affecting pulse shape, recharge phaseamplitude, recharge delay, and the like.

At 66, the modulated stimulation signal can be applied (by activatingone or more contacts of electrode 14) to the neural tissue of theindividual to affect the bodily function. As noted, the electrode can beplaced transcutaneously, subcutaneously, or directly on the neuraltissue to be stimulated. In some instances, the neural tissue that theelectrode can interface with can include a portion of the centralnervous system (e.g., for deep brain stimulation, spinal stimulation, orthe like). For example, deep brain stimulation can be used to treatmovement disorders, such as essential tremor or Parkinson's disease. Inanother example, deep brain stimulation and/or spinal cord stimulationcan also be used to manage pain. In other instances, the neural tissuethat the electrode can interface with can include a portion of theperipheral nervous system (e.g., a nerve (e.g., an afferent nerve, anefferent nerve, and/or an autonomic nerve) and/or ganglia). For example,the bodily function can be a sensory function (e.g., perception), anautonomic function, a motor function, an organ function, and/or acognitive function. In one example, the biological function can includesensory restoration in amputees. In another example, the biologicalfunction can include modulation of pain. In a further example, thebiological function can include restoration of taste. In yet anotherexample, the biological function can include regulation of swallowing.In still another example, the biological function can include regulationof gastric reflux. In yet another example, the biological function caninclude regulation of blood pressure, appetite, or the like. In still afurther example, the biological function can include restoration ofhearing, vision, or the like. In yet another example, the biologicalfunction can include restoration of sexual sensation or enhancement ofsexual sensation. In a further example, the biological function caninclude genito-urinary regulation, such as relieving incontinence,regulating voiding, and the like. In still another example, thebiological function can include regulation of a movement disorder.

For the different biological functions, electrodes can be placed indifferent areas of the individual's body and the patterned intensitymodulation of the stimulation signal can lead to recruitment ofdifferent populations of axons within the neural tissue. The electrodescan be placed transcutaneously, subcutaneously, or directly on theneural tissue to be stimulated. For example, in the case of nervestimulation, the electrodes can be placed on the patient's skin(transcutaneous electrical nerve stimulation).

FIG. 7 shows an example of a method 70 method for modulating theintensity of a signal that can be used for the neural stimulation. At72, a stimulation signal (e.g., SS) can be applied to neural tissue ofan individual (e.g., by electrode 14). In some instances, thestimulation signal can be a time-varying electrical signal. For example,the stimulation signal can include a plurality of pulses. Each of thepulses can have the same shape and/or a different shape (e.g.,rectangular, triangular, trapezoidal, sinusoidal, etc.). In someexamples, the plurality of pulses can be charge-balanced (e.g.,individually charge-balanced or a pattern of pulses can becharge-balanced). In other examples, the plurality of pulses can beapplied for a short time, so that the plurality of pulses need not becharge-balanced.

At 74, a feedback signal (e.g., FS) can be received (e.g., by receiver22) in response to the application of the feedback signal. For example,the feedback signal can include a user input, a feedback signal inputfrom the neural tissue or other tissue, a sensor signal input, a timeinput, etc. The feedback signal can include, for example, an inputrelated to a stimulation parameter and/or an input related to astimulation paradigm defining a modulation pattern or envelope. In someinstances, signal processing can be performed on the feedback signal(e.g., by receiver 22 and/or pulse generator 12). As an example, thesignal processing can transform the input signal into data related tothe input signal (e.g., PFS) that can be applied to modulate thestimulation signal.

At 76, an intensity parameter of the stimulation signal can be modulatedbased on the feedback signal (e.g., by pulse generator 12). In otherinstances, two or more intensity parameters of the stimulation signalcan be modified based on the stimulation signal. The modulation of theone or more intensity parameters of the stimulation signal related tointensity can recruit a different population of axons with each pulse.For example, based on the feedback signal, the intensity parameter canbe varied for each of the pulses. As another example, based on thefeedback signal, the intensity parameter can be varied for a pluralityof pulses according to a stimulation paradigm that defines a modulationpattern or modulation envelope (e.g., any time-varying shape, such as asinusoid, a triangle, a trapezoid, or the like). In some instances, asingle intensity parameter related to intensity can be modulated, whilein other instances, different intensity parameters related to intensitycan be modulated at different times and/or at the same time (orsubstantially the same time). Examples of intensity parameters that canbe modulated include amplitude, pulse width, interpulse interval, pulseshape, parameters affecting pulse shape, recharge phase amplitude,recharge delay, and the like. Other examples of intensity parameters caninclude a parameter related to the modulation envelope (e.g., shape,frequency, amplitude, etc.).

FIG. 8 shows an example of a method 80 for affecting a desired bodilyfunction with the neural stimulation. The neural stimulation can includepatterned stimulation intensity (or “Ψ-stim”) to recruit a population ofaxons to affect the desired bodily function. At 82, a stimulation signal(e.g., SS) with an intensity that is modulated with time (e.g., by pulsegenerator 12) can be applied to neural tissue of an individual (e.g., byelectrode 14). For example, the intensity can be modulated with timebased on a feedback signal. As noted, for example, the feedback signalcan include a user input, a feedback signal input from the neural tissueor other tissue, a sensor signal input, a time input, etc. As noted, theneural stimulation can be applied to a normal individual, an amputee, aparalyzed individual, a diseased individual, or the like.

At 84, a different population of axons in the neural tissue can berecruited with each pulse of the stimulation signal. For example, thepatterned stimulation intensity can be modulated with regard to timingand/or strength to alter an electric field delivered to the neuraltissue from each pulse. At 88, a desired bodily function can be affectedbased on the recruited population of axons. For example, the bodilyfunction can be a sensory function (e.g., perception), an autonomicfunction, a motor function, an organ function, and/or a cognitivefunction. In some instances, the patterned stimulation intensity can bespecific to affect the desired bodily function.

V. Additional Devices, Systems, and Methods

Neural stimulation with patterned stimulation intensity (or “Ψ-stim”)(e.g., according to the systems and methods discussed above) can beapplied in the peripheral nervous system and/or the central nervoussystem of: a normal, able-bodied individual; an amputee; a paralyzedindividual; or a diseased individual, such as an individual sufferingfrom an autonomic, motor, and/or sensory deficit to affect a certainbiological function. The patterned stimulation intensity allows thesignal to mimic actual biological signals, allowing the biologicalfunctions to occur more naturally than other types of stimulation.

One example application of neural stimulation with patterned stimulationintensity can provide a “virtual” sensation to an individual. Forinstance, a median, ulnar and/or radial nerve can be stimulated toprovide artificial sensation. In another example, the virtual sensationcan enable a sensory-enabled (e.g., touch, sight, hearing, taste, smell,etc.) virtual reality, user interfaces (e.g., to computing devices), andtelepresence.

In another example, the use of virtual sensation can include medicalapplications, such as a clinician performing a physical diagnosis of apatient from a remote location. Another example use of the virtualsensation can include virtual contact for gaming applications and/or toaugment social media by allowing an individual to virtually contactanother individual (e.g., to allow an individual to perceive thesensation of holding another individual's hand).

Another example can include use of an individual's fingers to enableperceived sensations that that the individual cannot otherwisephysically or safely experience. With such a system, a carpenter can usehis or her fingers to scan over a wall to feel a stud or wire instead ofusing conventional carpentry tools. In another example, an obstetriciancan feel a fetus' heart beat while performing an in utero exam. Inanother example, ultrasound information indicating an irregular tissuemass in the breast, abdomen, or other bodily location can be “felt” by aclinician. Current sensing tools convert physical information to visualinformation that the user interprets. With patterned intensitymodulation, a clinician may be able to better interpret and diagnose apatient using the sense of touch rather than, or in addition to, visionalone.

Another example use of virtual sensation can include robotic control, inwhich feedback from a robotics system (e.g., a drone pilot, a roboticaircraft, or the like) can be returned to an operator to improve controland operation of the robotics system by allowing the pilot can feel whatis happening in or to the aircraft.

Other applications of the present disclosure may include situationswhere it is unsafe to actually (physically) experience a sensation. Forexample, a mechanic can diagnose engine performance by “feeling”vibrations or temperature information from sensors inside an engine. Thepressures and forces within the engine would far exceed what could besafely felt, but the data from the sensors can be scaled and translatedto touch sensations according to the present disclosure.

From the above description, those skilled in the art will perceiveimprovements, changes and modifications. Such improvements, changes andmodifications are within the skill of one in the art and are intended tobe covered by the appended claims.

What is claimed is:
 1. A method comprising: receiving a sensor signal inresponse to an action configuring a stimulation signal with a pattern ofstimulation intensities based on the sensor signal; delivering thestimulation signal to one or more nerves of the individual, wherein theindividual experiences a virtual sensation based on the stimulationsignal being delivered to the one or more nerves of the individual. 2.The method of claim 1, wherein the individual is an amputee and thevirtual sensation is related to an amputated body part.
 3. The method ofclaim 1, wherein the individual is a diseased individual and the virtualsensation is related to a diseased body part.
 4. The method of claim 1,wherein the individual is an able bodied individual and the virtualsensation is related to an intact body part.
 5. The method of claim 1,further comprising: receiving another sensor signal in response toanother action; and reconfiguring the stimulation signal with adifferent pattern of stimulation intensities based on a differentvirtual sensation to be felt by the individual.
 6. The method of claim1, wherein the one or more nerves of the individual comprise a pluralityof sensory fibers, and wherein the stimulation signal is configured toactivate at least a portion of the sensory fibers.
 7. The method ofclaim 1, wherein the virtual sensation is related to pain relief.
 8. Themethod of claim 1, wherein the action is performed by or on a deviceexternal to the individual.
 9. The method of claim 1, wherein the actionis performed at a location of the individual and/or at a location remotefrom the individual.
 10. A system comprising: a pulse generatorconfigured to: configure a stimulation signal with a pattern ofstimulation intensities based on a sensor signal received in response toan action; and generate the stimulation signal; at least one electrodeconfigured to deliver the stimulation signal to one or more nerves of anindividual to cause the individual to experience a virtual sensation.11. The system of claim 10, wherein the one or more electrodes areconfigured to at least partially surround the one or more nerves. 12.The system of claim 10, wherein the individual is an amputee and thevirtual sensation is related to an amputated body part.
 13. The systemof claim 10, wherein the individual is a diseased individual and thevirtual sensation is related to a diseased body part.
 14. The system ofclaim 10, wherein the individual is an able bodied individual and thevirtual sensation is related to an intact body part.
 15. The system ofclaim 10, wherein the one or more nerves of the individual comprisesensory fibers, wherein the stimulation signal is configured to delivera sensation to the sensory fibers so that the individual experiences thevirtual sensation.
 16. The system of claim 10, wherein the action isperformed by the individual.
 17. The system of claim 10, wherein theaction is performed by or on a device external to the individual. 18.The system of claim 10, wherein the action is performed at a location ofthe individual and/or at a location remote from the individual.
 19. Thesystem of claim 10, wherein the virtual sensation allows the individualto experience a sensation when the individual otherwise would not beable to experience the sensation, wherein the pattern of stimulationintensities mimic actual biological signals.
 20. The system of claim 10,wherein the virtual sensation is related to pain relief.